chore: Update tsconfig target to ES2021

All targeted browsers support ES2021 syntax. This change provides an
immediate bundle size reduction, with the potential for further gains if
code is rewritten to take advantage of optional chaining and nullish
coalescing.

* Optional chaining:
  https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Optional_chaining#browser_compatibility
* Nullish coalescing:
  https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Nullish_coalescing#browser_compatibility

Author: TrevorBurnham

pages/tsconfig.json

@@ -1,7 +1,7 @@
 {
   "compilerOptions": {
-    "lib": ["ES2020", "DOM"],
-    "target": "ES2015",
+    "lib": ["ES2021", "DOM"],
+    "target": "ES2021",
     "declaration": false,
     "declarationMap": false,
     "rootDir": ".",

src/test-utils/tsconfig.json

@@ -1,11 +1,11 @@
 {
   "compilerOptions": {
+    "lib": ["ES2021", "DOM"],
+    "target": "ES2021",
     "strict": true,
     "incremental": true,
     "types": [],
     "module": "CommonJS",
-    "target": "ES2015",
-    "lib": ["ES2020", "DOM"],
     "declaration": true,
     "allowSyntheticDefaultImports": true,
     "outDir": "../../lib/components/test-utils",

tsconfig.json

@@ -1,7 +1,7 @@
 {
   "compilerOptions": {
     "lib": ["ES2021", "DOM"],
-    "target": "ES2015",
+    "target": "ES2021",
     "types": [],
     "module": "ES2015",
     "moduleResolution": "node",
@@ -15,11 +15,5 @@
     "incremental": true
   },
   "include": ["src", "types"],
-  "exclude": [
-    "**/__tests__/**",
-    "src/test-utils/**",
-    "**/__integ__/**",
-    "**/__a11y__/**",
-    "**/__motion__/**"
-  ]
+  "exclude": ["**/__tests__/**", "src/test-utils/**", "**/__integ__/**", "**/__a11y__/**", "**/__motion__/**"]
 }

tsconfig.unit.json

@@ -1,7 +1,7 @@
 {
   "compilerOptions": {
-    "target": "es2018",
-    "lib": ["es2020", "dom"],
+    "lib": ["ES2021", "DOM"],
+    "target": "ES2021",
     "types": ["node", "jest", "@testing-library/jest-dom"],
     "moduleResolution": "node",
     "downlevelIteration": true,